Food Chain and Food Web (Ecosystem) EVS, B. Pharmacy 1st Year, Sem-II
Self healing Bioconcrete.pptx
1. Biology for Engineers
21BE45
Self healing bio concerete
Ms. Supreetha K
Assistant Professor
Department of Biotechnology
Dayananda Sagar College of Engineering
Bangalore
supreetha-bt@dayanandasagar.edu
9916315305
2. Biology for Engineers
Trends in Bioengineering
Self healing bio concrete
• Concrete is one of the most widely used construction materials and has a high tendency to form
cracks.
• These cracks lead to significant reduction in concrete service life and high replacement costs.
• Although it is not possible to prevent crack formation, various types of techniques are in place to
heal the cracks.
• It has been shown that some of the current concrete treatment methods such as the application of
chemicals and polymers are a source of health and environmental risks, and more importantly, they
are effective only in the short term.
• Thus, treatment methods that are environmentally friendly and long-lasting are in high demand.
• A microbial self-healing approach is distinguished by its potential for long lasting, rapid and active
crack repair, while also being environmentally friendly.
• Furthermore, the microbial self-healing approach prevails the other treatment techniques due to
the efficient bonding capacity and compatibility with concrete compositions.
Self healing bio concrete
3. Biology for Engineers
Trends in Bioengineering
Self healing bio concrete
• Bio-concrete is a self-healing form of concrete designed to
repair its own cracks.
• It was developed by Dutch researcher and microbiologist
Hendrik Jonkers using an extra ingredient acting as a
healing agent and requires no human intervention to be
repaired once placed.
• Bio-Concrete set to revolutionize the building industry.
• His vision was to develop a bionic approach that improves
the tensile strength and eco-friendly properties of concrete.
• The Dutch researcher set out to develop the bio-concrete of
the future with limestone producing bacteria that can
survive in a concrete structure for up to 200 years, and
which “awaken” when damage occurs, enabling them to heal
the cracks.
What is Bio-Concrete?
4. Biology for Engineers
Trends in Bioengineering
Self healing bio concrete
• Self-healing octopus tentacles or plants that create new organisms with offshoots served
as inspiration for Jonkers’ invention.
• To heal cracks in the concrete, Jonkers chose bacteria (Bacillus pseudofirmus and B.
cohnii), that are able to produce limestone on a biological basis.
• The positive side-effect of this property: the bacteria consume oxygen, which in turn
prevents the internal corrosion of reinforced concrete.
• These bacteria do not pose a risk to human health, since they can only survive under the
alkaline conditions inside the concrete.
• Based on these findings, Jonkers and his team of researchers developed three different
bacterial concrete mixtures: self-healing concrete, repair mortar, and a liquid repair system.
• In self-healing concrete, bacterial content is integrated during construction, while the repair
mortar and liquid system only come into play when acute damage has occurred on concrete
elements.
5. Biology for Engineers
Trends in Bioengineering
Self healing bio concrete
• Bacterial spores are encapsulated within two to four
millimeter wide clay pellets and added to the cement mix
with separate nitrogen, phosphorous and a nutrient agent
(calcium lactate).
• This innovative approach ensures that bacteria can
remain dormant in the concrete for up to 200 years.
• Contact with nutrients occurs only if water
penetrates into a crack and not while mixing cement.
• This variant is well-suited for structures that are
exposed to weathering, as well as points that are difficult
to access for repair workers. Thus, the need for expensive
and complex manual repairs is eliminated.
